The present disclosure relates generally to electric motors and more particularly to methods and systems for use in cooling an electric motor.
Electric motors generate heat during operation as a result of both electrical and mechanical losses. Typically, an electric motor must be cooled to facilitate the desired and efficient operation of the motor. Moreover, an excessively high motor temperature may result in motor bearing failure or damage to the stator winding insulation.
Electric motors generally have an enclosure including a frame and endshields. The most common enclosures are either “open” or totally enclosed. With an “open” enclosure, ambient air circulates within the enclosure, and heat is removed by convection between the air and heat generating motor components within the enclosure. The heated air is exhausted out from the enclosure. In contrast, totally enclosed type enclosures typically are used in applications in which airborne contaminants, e.g., dirt, oil, or mist, must be prevented from entering within the enclosure. Both convection and conduction type cooling occurs within the enclosure, and some convection cooling occurs along the external surfaces of the enclosure. For example, forced convection cooling is provided by a fan directly mounted to the motor shaft external to the enclosure that forces air over the frame and endshields. In particular, the fan is directly mounted on the shaft using a keyway or a bolt mechanism. During motor operation, the fan rotates at the same speed as that of the motor.
Manufactures have developed various types of fans and fan covers for cooling different types of motors. The various types and forms of fans depend on motor considerations such as the pole of the motor, direction of rotation, space consideration to maintain the footprint of the motor, regulatory requirement and noise levels. The cooling performance is based on the motor characteristics in which the fan operates. Accordingly, manufacturers are required to develop, install and maintain multiple variations of fans and fan covers for different motors. Operating with the wrong fan and/or fan cover may decrease performance of the motor and/or cost inefficiencies for motor cooling.